Blasting device



March 18, 1930. J. MORA BLASTING DEVICE Filed Dec. 5, 1928 Patented Mar. 18, 1930 T g; F FE Q E JOHN MORA, OF PLAINS, PENNSYLVANIA BLASTING DEVICE Application filed December 3, 1928. Serial No. 323,367.

This invention relates to a simple and of ficient device to facilitate the proper charging of blast-holes in mines when using electrical detonators.

The primary object of the present invention is to provide means to facilitate proper positioning of the dctonator in the shot-hole and to protect the conductor wires of the detonator against damage or breakage while ramming the tamping material in the shothole.

A further object is to provide a device of the above kind embodying a tube and means to thread the conductor wires of a detonator through said tube, said tube being rigid and of alength to enclose and protect the portion of said wires adapted to lie in the shot-hole.

Other objects will become apparent as the nature of the invention is better understood,

and the same consists in the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawing, and claimed.

In the drawing:

Figure 1 is a section through a shot-hole with the wire protector of the present invention positioned therein.

Figure 2 illustrates the manner of threading the conductor wires of the detonator through the protecting tube, the latter being in longitudinal section and the threading rod being disposed therein and shown in elevation; and

Figure 3 is a plan View of the protecting tube.

Referring more in detail to the drawing, 5 indicates the seam of coal to be blasted, in which is drilled the usual shot-hole 6.

The present invention embodies a rigid elongated metallic or other suitable tube 7 having an open axial bore and preferably tapered externally and gradually from one end to the other, as shown. This tube is of approximately the same length as the shot-- hole and has a hand hold or loop-like handle 8 rigid with its larger outer end, and positioned to one side of the bore of the tube as seen in Figures 1 and 2.

The invention also embodies a rod 9 of 59 a diameter somewhat smaller than that of the bore of the tube 7 and freely slidable therethrough, said rod being somewhat longer than the tube and having means, such as an eye 10, on at least one end thereof to facilitate connection of the conductor wires 11 of an ordinary electrical detonator 12 thereto. As shown, the rod 9 has an eye at each end, so that the wires may be connected to either end, depending upon which end of the rod is inserted into the tube. The explosive powder 60 or other explosive material is shown at- 13 and the tamping material at 14.

In practice, the charge of explosive at 13 is placed in the shot-hole at the inner end of the latter, and the rod 9 is inserted in the tube 7 so as to project at one end beyond the small end of the tube. The wires 11 are then connected to this projecting end of the rod 9, whereupon the rod is withdrawn from the tube at its larger end so as to thread the wires through the tube and position the detonator 12 at the smaller end of the latter. The tube is then inserted in the shot-hole so as to position the detonator adjacent the explosive charge, the wires 11 having the portions thereof within the shot-hole enclosed by the tube. The tamping material lt is then rammed in place above and around the tube and behind the explosive charge and the detonator, and the apparatus is then ready for the blast which may be effected by connection of the wires 11 with suitable electrical firing apparatus.

Due to the tapered form of the tube, it may be readily drawn from the mineral for re-use after each blasting operation. Also the handle 8 is arranged so as to not interfere with the manipulation of the threading rod 9, and, due to the fact that the portion of the wires within the shot-hole is enclosed by the tube, they are protected against damage or breakage while tamping the material 1% in the shot-hole. The material 14 may therefore be safely tamped very solidly in the shot-hole to insure loosening of a maximum quantity of coal with a given explosive charge for each blast.

Minor changes may be made without departing from the spirit and scope of the invention as claimed.

What I claim as new is: v p

1. VA blasting device'of the character described, comprising a tube, for receiving the conductor wires of a detonator therethrough, said tube being rigid and of a length to en- 'close and protect the portion of said wires adapted to lie in the blast-hole, said tube further being externally tapered from one end to the other and having a rigid handle on its larger end arranged to extend outwardly and upwardly therefrom.

2. In a blasting device of the character described, a rigid tube adapted to have the conductor wires of a detonator threaded therethrough, said tube being of a length to enclose and protect the portion of said wires adapted to lie in the blast-hole and being gradually tapered externally from one end to the other, and a handle on the larger end of said tube, said handle being integrally formed with the tube and disposed to extend outwardly and upwardly therefrom.

In testimony whereof I aflix my signature.

JOHN MORA. v 

